High Definition may sound like a great choice to make your documentary film look amazing, but its limitations are still to constricting.
Rebel With a Camera
Rebel filmmaking, as some call it, is based on the idea that you are going to make do with less resources so that you maintain an integral freedom in your work. Through this you will often have to scrounge together resources, crew members, and technology wherever you can get it. This can mean that you will have to be able to use any camera given to you and jump on whatever computer happens to have non-linear editing software. At no point in this should you set a standard that will then limit your ability to work spontaneously with available resources. This is exactly what employing high definition would do.
The Last Temptation
High definition is the buzz word right now because it is the natural next step in video quality. At some point in the near future all media will then restructure themselves around this new standard. This may inspire some to believe that they should not use archaic digital video technology to film their footage, but the opposite is actually true.
One of the first things that we have to remember is that the cameras themselves are much more expensive and rare. If you are going out and purchasing a digital video camera for your documentary you will have to make do with significantly fewer features or an obscene price if you want to get high definition capabilities. If you are looking to cheaply rent or check out a camera from an educational or film institution you are going to have a much smaller chance of actually being able to use the camera consistently. Most of these locations still only have a few high definition digital video cameras so you are definitely going to have to share most of the time.
Tapes n' Tapes
Added to this expense is the possible added cost in digital video tapes. This is not always true, but is usually. Since the high definition video is much larger in size you may have to go through many tapes, or even use an alternative digital storage device, to actually use it for filming. Because of this you may have to be more selective of what you film, which lowers your creative ability.
The Chopping Block
When it comes to editing, high definition is going to limit you the most significantly. Most editing systems are simply not equipped to handle high definition, so you would have to find a specialty location to do all of your editing. Instead of having a portable hard drive that you can take from computer to computer for editing in different locations you may have to remain stationary.
For DVD authoring you will also be much more limited. Regular DVDs will not be able to show true high definition video, so putting your HD film onto a regular DVD will not look the way you intended. You will have to put it onto HD DVD or Blu-ray, which are much more expensive and are still unable to be viewed by most households. If you just make a high quality standard definition film you can still place it onto a Blu-ray disc so that people with those players can watch it.
Freedom Over Definition
The truth is that the infrastructure for high definition is not accessible enough to employ for guerilla filmmaking. If you are filming on high definition and then you lose access to the HD camera you will not be able to match it up with another digital video camera. Right now a basic camera is still fine, and it will have to be until high definition because more integrated.